FIX: sets categoryId but do not scope when replying as new topic (#7002)

app/assets/javascripts/discourse/controllers/composer.js.es6

@@ -783,7 +783,11 @@ export default Ember.Controller.extend({
     });
 
     // Scope the categories drop down to the category we opened the composer with.
-    if (opts.categoryId && opts.draftKey !== "reply_as_new_topic") {
+    if (
+      opts.categoryId &&
+      opts.draftKey !== "reply_as_new_topic" &&
+      !opts.disableScopedCategory
+    ) {
       const category = this.site.categories.findBy("id", opts.categoryId);
       if (category) {
         this.set("scopedCategoryId", opts.categoryId);

app/assets/javascripts/select-kit/components/composer-actions.js.es6

@@ -242,6 +242,7 @@ export default DropdownSelectBoxComponent.extend({
   replyAsNewTopicSelected(options) {
     options.action = CREATE_TOPIC;
     options.categoryId = this.get("composerModel.topic.category.id");
+    options.disableScopedCategory = true;
     this._replyFromExisting(options, _postSnapshot, _topicSnapshot);
   },
 
@@ -295,7 +296,12 @@ export default DropdownSelectBoxComponent.extend({
       if (this[action]) {
         let model = this.get("composerModel");
         this[action](
-          model.getProperties("draftKey", "draftSequence", "reply"),
+          model.getProperties(
+            "draftKey",
+            "draftSequence",
+            "reply",
+            "disableScopedCategory"
+          ),
           model
         );
       } else {